13.2 g of a sample of zinc sulphate, ZnSO4.xH2O, was strongly heated until no further change in mass was recorded. On heating, all the water of crystallisation evaporated as follows: ZnSO4.xH2O  ZnSO4 + xH2O.
Calculate the number of moles of water of crystallisation in the zinc sulphate sample given that 7.4 g of solid remained after strong heating.
Are you finding the value of x, or are you finding the moles of water without putting it in a ratio

(Original post by ElectronDonor)
13.2 g of a sample of zinc sulphate, ZnSO4.xH2O, was strongly heated until no further change in mass was recorded. On heating, all the water of crystallisation evaporated as follows: ZnSO4.xH2O  ZnSO4 + xH2O.
Calculate the number of moles of water of crystallisation in the zinc sulphate sample given that 7.4 g of solid remained after strong heating.
Are you finding the value of x, or are you finding the moles of water without putting it in a ratio

Yeah, it says to find the moles of the water, so if you look at the balanced equation
ZnSO4.xH2O -> ZnSO4 + xH2O
x would be the number infront of the water, so as you said, just find x as usual